Ball-and-socket implement coupler



Sept. 6, 1949. H. P. WOLFRUM BALL AND SOCKET IMPLEMENT COUPLER 2 Sheets-Sheet 1 Filed July 17, 1947 InvenZZr.

5 rnqy' H. P. WOLFRUM BALL AND SOCKET IMPLEMENT COUPLER Sept. 6, 1949.

2 Sheets-Sheet 2 Filed July 17, 1947 nzlenzor HAROLD P WOMZUM fig 1U Patented Sept. 6, 1949 UNITED STATES PATENT Q-F-FICE I e 7 2,481,461 1 'BAYII'L-AND-SOCKET IMPLEMENT COUPLER Harold P. Wolfruin, Defiance, ohie Application July 1'7, 1947, SeiiitlNo. 76 15645 2 Claims. (01. 280-3317) 1 The present invention relates torimprovements in implement couplers and 'pole "supports and more particularly resides in a tractor hitch whereby the tractor may automatically couple to such implements as combines, corn pickers,

wagons, trailers and the like.

'An object of the invention is to provide an improvedcoupl'er in which the coupling action will be automatic and incident to the backing of the tractor to the coupler in which a ball carried 'by'a pole on the coupler is directed between normally 'open' jaws'on the tractor, the jaws being so pivotally arranged and constructed that in moving-into the'same the ball will automatically close the'jaws thereon and efiect the locking engagement between the two parts of the coupler.

A further object of the invention resides in providing an improved locking means by which the jaws are retained in the locked position upon the implement ball until such time as positive'r'elease is effected as'by the pulling of a cable by the operator of the tractor from a position con- 'venient to'his seat.

A still further object of the invention resides in providing'an-improved frame structure capable .of'easymounting upon the draw bars of the tractor and carrying the pivoted jaws in a compact manner in combination with a'hinged and freely movable gathering 'apron which automatically guides the ball to a'position'between the jaws.

With the foregoingand other objects in view the invention will'be more fully described hereinafter and'more particularly pointed out in the appended claims a I M In the dra'win "s-in' which like reference characters refer to like parts throughout the several views Figure 1 is a top plan view of an improved implement coupler "constructed in accordance with the present invention with the jaws in the closed position,

Figure 2 is a side elevational view of the same with "parts broken away and parts shown in section, t

Figure 3 is a view similar to Figure l'but with the jaws open,

Figure 4 is a rear elevational view taken from the left end of Figure 3 with the tractor draw bar omitted,

Figure 5 is afront elevationalview of the tractor unit with the gathering apron removed and taken from the right-hand end of Figure 2,

Figure 6 is a fragmentary perspective view. taken on an enlarged scale, of the locking device shown in the locked position, and

Figure '7 is a similar view with the parts in the release position. 7

Referring more particularly to the drawings, Ill designates a ball carried upon a pole 1 l which is attached to and projects forwardly from an implement, such as -a combine, corn picker, wagon,'trailer or the'like.

On the tractor there is the usual longitudinal tractor edraw bar 13 and in some cases a cross 'draw'bar' l l.

The tractor element of the coupler is carried upon a'base plate l5 having upstanding side walls it which receive 'therebetweenthe rear end of the longitudinal draw bar 13, the latter being held "thereto and centered "therein by a number of screws ll which are thr'eadedly engaged through the walls l6 and have lock'nuts It by which the I screws are "retained in adjusted position.

Below the plate FSaredependi'ng walls [9 having recesses 20 for receiving the cross draw "liar M.

A bolt-21 passes through registered openings in the draw bars and in the base plate Hi. The head of this bolt 22 is shown as resting upon the'uppersurface-oi the draw bar l3,'while'a nut 23 threaded on the bolt 2| engages beneath the cross draw b'ari l.

In the forward portion of the plat 15 are "arc'iiate slots 24 extendingg'enerally transversely orthe plate. ln -lateral'extensions 25 of the base plate l5 are longitudina'lslots 26 in'which play ro'cker bolts 2-! *niade 'fast on a rock shaft 28 aaapted to=be rotated by a lever 29 which extends afioiie sideof'the' b ase pl'ate'l5. A cable release slits attached tb'the lever 29 and runs to a positiofn convenient to the '(lrivers'seat' of the tractor.

iNp'ai'r-oi hemispherical jaws -3 I being counterpartsofthe bal-l lii arerotatably'mounted about pivots 32 havingsubstantially vertical axes. The

saw 31 may be carried 7 by webs'3'3 which directly 'r'eceive the pi-vot pins '32, such pivot pins being "carried in 'Baririgspacers 34 mounted upon the p'latel fi.

"Depending from the forward edges of the webs 3'3 whichin effectform-parts of the jaws 3| are look striker flanges 35 having downwardly extendingapins 36 *ternii'nating'at their lower ends in enlarged :heads 31. The pins slide in the arcuate slots 24 in accompaniment to the pivotal movement of the-jawsfil about their axes 32, for

which compare Figures 1 and 3. The slots 24 are struck on radii from the centers of the pins 32.

A gathering apron 39 depends at the rear of the tractor unit and is formed with upstanding flanges 40 which converge forwardly and provide a restricted throat 4| leading to the space between the jaws 3|. The apron has a pivotal movement in a vertical plane by reason of the fact that the forward ends of the flanges 45 are carried by the pivots 42, such pivots being mounted in the upper ends of vertical arms 43 carried upon the forward ends ofthe walls l9. These arms also carry a stop step 44 which extends rearwardly therefrom at a stepped down distance below the plate l5 and rearwardlyfof the pivots 42. In other words this step 441s positioned to receive the gathering apron 39 and. I

"the passage of same therethrough.

supports it in a properly inclined position to in tercept the ball I I]. The pivotal mounting. 42 of the apron 39 permits the same to automatisition.

wardly and downwardly to form a curved throat *fioor 45 which in-the lowered position of the apron forms a continuation of the apron floor to; guide the ball I!) into the socket provided by the jaws3l.'- .H Y

A coil spring 46 is connected to the free end of the lever 29 and the stop step 44 in order to bias the rocker bolts 21 to a locking position.

In the use of the device, an implement equipped with the pole H and ball Ii! is so arranged that the ball I 0 rides up the apron as the tractor moves backwardly: The ball will thus be guided tothe throat 4| and over the floor 45 and thus into the space betweenthe'jaws 51 which are at this time in the open condition shown in Figure 3. The'act of the ball .I ll entering the jaws will strike the forward portions of the same which are oifset inwardly from the pivots 2, thus rotating the jaws mutually toward one another and upon the ball In so that theball becomes clamped tightly therebetween. Thismotion is guided by the pins 36 moving in the arcuate slots 34. These pins also engage the curved walls of the slots 24 andstabilize the jaws 3! and their webs 33. The pins 36 and slots 34 perform a further function in that the end walls .of the slots 24 act as stops when engaged by the pins 36 particularly in arresting the opening movements of the jaws beyond a point where the ball It could properly strike the forward portions of such jaws to effect the automatic locking movement heretofore described. 1

When the jaws are thus closed togethergthe rocker bolts 2! which are held in the forward position by the lock strike flanges35 when the jaws are open are permitted to rotate backwardly in slots 26 moving across the outer ends of the 'flanges 35. This movement is achieved byythe spring 46 as soon as the flanges 35 clear the slots 26. l a v. The implement is now eifectually hitched to -the.trac tor and can be drawn about the field to perform its essential operations; When the implement is to be released from the tractor, the operator pulls upon the cable orwchainflfi which rotates the lever 29 and the rockingubolts 21 forwardly to release the bolts from blocking the outer ends of the flanges 35; thus permitting the jaws to be opened; and as soon as opened the flanges 35 interpose barriers to'the return forward movement of the rocker bolts 21. Thus as v cally rise when the tractor passes over obstacles that encounter the apron in thisjlowered p0- long as the jaws 3| remain in the open position, the spring 46 is stretched under tension and possesses the necessary potential energy to lock the jaws immediately they are closed by the action of the ball H] in entering between same.

The device provides for automatic uncoupling in that when the cable release 30 is pulled forwardly to rock the locking bolts 21 forwardly outv of the paths of the. flanges 3 5, the tractor may be driven forwardly, whichwilljreact to cause the rear curved portions'of the jaws to slide outwardly away from the ball permitting It will be understood that I have disclosed only .one embodiment of which the invention is susceptible but such invention may be incorporated v ,in a variety of forms all of which are within the V purview of the invention provided the same fall within the scope of the following claims.

:withdrawing said locking means from sition to permitlopening of the jaws.

Number I claim: 1 1. An implement couplercomprising "a plate, means whereby said plate is attached-to the rear portion'of a tractor, side extensions on said plate having longitudinal slotsv therein, rocking bolts playing in said slots, means for biasing said bolts to a rear locking position, means for swinging said bolts to a forward release, positiom pivoted jaws above and adjoining said bolts having dependent parts adapted to' engage the sides of the bolts'whenthe jaws are closed and adapted to extend in rear of the bolts when thejaws' are open to prevent the bolts from moving 'to locked position,'and a ball adapted to be'carried by the implement for entering between. said jaws.

2. For use with a vehicle, an implement'coupler comprising a ball on the implement and a socket on the-tractor, said socket formed from laterally -movable' jaws having forward parts extending into the 'path 1 of the ball whereby the jaws are closed on the ball by the rear movement of the jaws with reference to the ball, said jaws being pivoted to. swing. in a substantially horizontal plane with the pivots arranged at'the forward outer corner. portions of vth'e jawsja support on the'vehicle .for said jaws having arcuate slots therein struck from the centers of the pivots,

:guide and stop pins on said jaws slidable in said arcuate slots, normally locked means for engaging the side portions of said jaws for preventing theaccidental opening of the jaws, and means for locked po- HAROLD P. 'WO'LFRUM,

-. REFERENCES orfEn UNITED STATES PATENTS Name Date 529,396 Lohr Nov. '20,]189 l 1,336,18l 'Anderson "Apr. '6, 1920 1 1,354,589 Thoreson Oct. 5, 1920 2,056,525 Johnson et a1. Oct. "6, 1936 2,078,851 Hovey Apr; 27, 1937 2,151,181 Appell Mar. 21, 1939 2,159,395 Mersereau -May 23, 1939 2,230,242 :Goodrich -Feb. 4-, 1941 2,322,446 Hudson' June 22, 1943 2,347,033 Daton Apr. 13, 1944: 

